From Curiosity to Addiction: The Devastating Effects of Nicotine on Adolescent Brains
When a person takes in nicotine through smoking cigarettes or using vaping devices that resemble pens, thumb drives, or candy jars, the body releases a chemical called adrenaline. This binds to the brain’s reward systems and triggers a feeling of pleasure.
The adolescent brain is still maturing, and the medial prefrontal cortex (mPFC) is especially sensitive to the long-term effects of nicotine exposure. These include deficits in attention performance.
Addiction is an intense craving for something that interferes with normal control over behavior. It changes the brain, subverting its ability to register pleasure and corrupting other normal drives like learning and motivation. It also disrupts healthy relationships and responsibilities. According to CA tobacco experts, teens with addiction often have a lack of motivation to engage in positive activities. They are more likely to take risks that lead to problems, such as getting involved with drugs or alcohol.
Teens who abuse substances tend to do so for a variety of reasons: curiosity, peer pressure, or a desire to feel better about themselves (to relieve stress, forget their problems, or feel more alive). Over time, addictive drugs and behaviors change the way your brain responds to pleasure, meaning they no longer provide as much satisfaction. The drug or activity alters your brain’s normal reward circuitry by flooding it with dopamine. In addition, your brain’s memory center (the hippocampus) lays down memories of this rapid sense of reward.
Curiosity is a powerful emotion that leads many teens to explore the world around them. This curiosity can be positive, such as trying new foods or hanging out with friends. However, it can also lead teens to take dangerous risks, like using drugs. During adolescence, the brain is undergoing major changes. One important change is that unused connections in the brain are pruned away while used ones are strengthened. This pruning is part of the brain’s way of becoming more efficient, based on the “use it or lose it” principle.
Researchers have also found that the brain’s gray matter reaches its maximum volume in adolescence. This is especially true for the prefrontal cortex, a brain region involved in social processing and impulse control. This mismatch between brain development and the need to interact with peers may explain why some adolescents are impulsive, reckless, and irrational.
Adolescents who use party drugs, such as cocaine or ecstasy, may be especially vulnerable to these kinds of behaviors because they believe that they must experience as much as possible in life before they become adults and have responsibilities. This attitude can be reinforced by the sex appeal of these substances and their association with party culture.
During adolescence, the brain is at an especially vulnerable point. The limbic system that controls cognition, emotion, and drug reward matures during this period. Adolescents show a unique sensitivity to nicotine. Acute nicotine exposure changes the activity of specific neurons in adolescent brains that process information about rewards and consequences. These effects are long-lasting and can impact future trajectories of behavior, including risky behavior such as substance use.
The prefrontal cortex, which plays an essential role in regulating mood and impulse control, is immature during adolescence. This means that, at the moment, it may not be able to stop an adolescent from taking a dangerous risk. The prefrontal cortex depends on the more developed amygdala to weigh the consequences of a risky decision before it is made. However, the amygdala can override the PFC during emotional stress or peer pressure.
In addition, the circuitry that connects the prefrontal cortex and the dopamine system still develops during adolescence. During this time, the dopamine system is particularly sensitive to the rewarding properties of nicotine. Adolescent rodents respond to nicotine with more excitement in conditioned place preference experiments than adult rats. Acute nicotine treatment also increases the number of active adolescent neurons in the dopamine system.
Nicotine is an addictive chemical that is present in cigarette smoke, e-cigarette liquid and vapor, cigars, and chewing tobacco. It is also found in nicotine replacement therapies such as gums and patches. When ingested, nicotine is absorbed through the oral mucosa and enters the bloodstream, where it undergoes pharmacological effects in the brain and body. In the brain, it triggers dopamine release in reward circuits and causes a craving for products containing nicotine. Nicotine stimulates the release of neurotransmitters such as dopamine, glycine, and glutamate. It also binds to nicotinic receptors in the prefrontal cortex (PFC), which modulates information processing and control.
The adolescent brain is particularly vulnerable to the damaging effects of nicotine. It has not fully matured, which may explain why adolescents progress faster to nicotine dependence than adults, find smoking more rewarding, underestimate the risks of smoking, and are more influenced by the behavior of their peers.
Adolescent rats have a greater sensitivity to nicotine than adult rats in intravenous self-administration tests and conditioned place preference studies, even with low schedules of reinforcement. This increased sensitivity to nicotine is associated with the immature state of nAChRs in the adolescent brain, as shown by in vitro rubidium efflux assays and in vivo microdialysis in ventral striatal slices.
The PFC is one of the brain’s last regions to develop fully during adolescence, and studies in rodents have shown that nicotine exposure alters acetylcholine and glutamate signaling at prefrontal synapses. This can lead to a decrease in cognitive function and attention performance, which are the same problems observed in people who smoke cigarettes or use non-combustible nicotine products.